.container{
    width: 1000px;
    margin: 0 auto;
}

.banner{
    height: 100px;
    background: lightgray;
}

.left{
    width: 300px;
    height: 300px;
    background: darkgreen;
    float: left;
}
.right{
    width: 700px;
    height: 300px;
    margin-left: 300px;
    background: darkorange;
}

.footer{
    height: 100px;
    background: lightgray;
    text-align: center;
    line-height: 100px;
}